SOLUTION TO LAST MONTH'S QUIZ
1. 720
2. 1/6
3. 2/3
Notes.
Q.1. 6*5*4*3*2*1 = 720
Q.3. Of the first four candidates, the best among them is equally likely to be number 1, 2, 3 or 4.
So of the 720 (equiprobable) permutations of all six, the number in which the fourth is the best so far = 720/4 = 180.
Of these, the number in which the fourth is best overall = 720/6 = 120.
So the required probability = 120/180 = 2/3.
